Aluminum Conductor Steel Reinforced (ACSR) cable is a high-capacity, high-strength stranded power cable used as electrical conductors in overhead power lines. The outer strands in an ACSR cable are aluminum. Aluminum has very good conductivity, low weight, and relatively low cost. The center strands (i.e. core) in an ACSR cable are made of steel, which provides extra strength for the ACSR cable. The lower electrical conductivity of the steel core has only a minimal effect on the overall current-carrying capacity of the cable due to the “skin effect.” With the skin effect, most of the current in an ACSR conductor is carried by the aluminum portion of the cable. Consequently, the higher resistance of the steel strands has only a small effect on the cable's overall resistance.